INFLUENCE OF FODDER CROP ROTATIONS ON CROP CONFERENCE AND PRODUCTIVITY OF AGRICULTURAL CROPS IN BAIKAL REGION

Abstract

The research was carried out in Irkutsk region in 2011–2014. The purpose of this work is to study the influence of forage crop rotations on the degree of weediness of fields and the yield of forage crops. The objects of research are three forage crop rotations: one control without perennial legumes (meadow clover) and two with meadow clover in the structure of sown areas of 20 and 40%. The soil of the experimental site is gray forest heavy loamy, with the following characteristics: salt extract pH 4.7 ... 4.9, humus content 4.5 ... 4.8%, mobile phosphorus - 160 mg/kg, potassium - 130 mg/kg. The least amount of weeds in the experiment was in variants with perennial leguminous grasses (7 ... 9 pcs/m2), which ensured an increase in yield by crop rotation on average for 4 years of research by 14 ... 19%. The most contaminated was the control crop rotation. The greatest number of weeds in this crop rotation was noted in the crops of corn and pea-oat mixture - 5 ... 12 pcs/m2. Of the juvenile weeds, mainly gray mice (Setaria glauca (L.) Beauv.), wild radish (Raphanus raphanistrum), of perennial weeds, yellow sow-thistle (Sonchus arvensis L.) and field horsetail (Equisetum arvense L.) prevailed. Weediness of crops did not have a significant effect on the yield of forage crops in the links of crop rotations. Among the five-field crop rotations, the highest productivity was observed in the variant with two fields of meadow clover (2.5 thousand fodder units/ha) with the content of digestible protein in 1 fodder unit 99.1 g